In the field of modern integrated circuit devices, and in particular in the field of integrated circuit devices for mobile or wireless applications, there is often a trade-off between reducing power consumption whilst increasing performance. In order to accommodate both requirements sufficiently, it is necessary to implement ‘on-chip’ power management. A critical part of such on-chip power management is the use of voltage regulators.
In order to achieve a maximum operating frequency for an integrated circuit device, accurate voltage control is necessary, which requires high accuracy voltage regulators. By providing an on-chip regulator with good feedback of the relevant output voltage, a high degree of accuracy is typically achievable for the supplied voltage. However, inaccuracy in the output voltage can still occur, for example due to abrupt load changes that cause ripples in output voltage.
One method for compensating for such high load changes is to implement a high comparator gain within the voltage regulator. However, such a high comparator gain impacts the system stability, in particular at low load current states, and thus is undesirable. Some known solutions propose implementing different regulator modes, whereby the different modes of the regulator provide, for example, better stability at lower load current states and better response times at higher load current states. However, in practice it is typically not possible to reliably distinguish between the states in a real system, thereby resulting in improper operation of the regulator.